Process of producing homogeneous porous materials



M. o. SEM

Filed May 15, 1920 2 sheets-sheet 1 Inventor',

Mathias @vrom Sem,

:EN im By i Attorneys PROCESS OF PRODUCING HOMOGENEOUS P OROUS MATERALSJune l2, 1923.

June 12, 1823. 1,458,858

l M. Q. SEM

PROCESS OF PRODUCING HOMOGENEOS POROUS MATERIALS Filed May 15 .l 1920 A2 sheets-sheet 2 Inventor., Mathias @vrom Sem,

l AttoTnqy-S.

Patented June 1,2, 1923.

` HATEIAS OVROM SEM, F .CHRISTIANIA, NORWAY, ASSIGNOR TO \DET NORSKEETIESELSKAB FOR ELEKTROKEMISK BANK, OF CHBISTIANIA, NORWAY.

INDUSTRI, NORSK INIDUSTRI-HYPO'IEK-lv PROCESS 0F PRODUCING HOMOGENEOUSPOROUS MATERIALS.

Application filed Hay 15, 1920. Serial No. 381,717.

To all 'whom it may concern:

Be it known that I, MATHIAS OvRoM` SEM, a subject of the King of Norway,and a resident of Christiania, Kingdom of Nor- Way, have inventedcertain new and useful Improvements in the Processes of ProducingHomogeneous Porous Materials, of which the following is a specification.

This invention relates to porous materials and more particularly to thattypeof porous materials which is used as or in the manufacture ofbuilding materials and for insulating pur oses.

The o ject of the invention is a process whereby crous melts may betreated in order to oitain a final product of high porosity.

By a suitable treatment of slags or other melts it is possible toproduce a foam which may be cast in moulds. Upon cooling solid porouspieces of the desired form will then be obtained. I have described sucha process in m prior United States patent application, erial No.345,445.

I have found that the foaming operation may be carried out with thegreatest facility,

when the foam produced has a high fluid? ity. The removal of the foamfrom the foaming apparatus will then cause no trouble` and the wholefoaming operation will run smoothly. On casting or moulding such fluidporous material difliculties arise which are not noticeable if thematerial has a comparatively low fluidity.

I have thus found that if a very .fluid foam is cooled in moulds in theusual manner, the exterior pa'rts of the finished product possess ahomogeneous structure, while the interior parts are filled withcomparatively large bubbles or cavities. The reason for this must bethat a comparatively rapid cooling takes place in the exterior parts ofthe mass, while the interior for a comparatively long time remains at ahi h temper ature. Therefore the bubbles in t e interior of the mass tosome extent burst and form l r bubbles, which have a tendency to riseam?e enlarge b absorbing smaller bubbles. From this o servation I havearrived at the conclusion that if the whole mass be rapidly andthoroughly cooled before being cast, it would uni ormly reta-in itshomogeneous structure, even if the final cooling is carried out veryslowly.

any desired form when employing highly fluid foam. As mentioned abovesuch foam may easily be removed from the foaming apparatus, runningtherefrom more regularly than foam of lower fluidity, and accordj ing tothe present inventionI I avoid all difficulties connected with thecastingand moulding of the highly fluid foam.

My method broadly consists in subjecting the foam or porous melt to betreated to the action of one or more cooling bodies, which press themass to a comparatively thin sheet, thus coolingr the whole mass In thismanner a rapid and thorough cooling is effected. The temperature of thecooling bodies is regulated so as to give-the foam a sufiicienltplasticity for casting or moulding after hav',-v ing passed the coolingbodies. i

I may increase the eflect of the cooling by directing water or coldgases on the porous mass after it has passed the cooling bodies.

It is of course impossibleto give a definite temperature as the mostsuitable for moulding the cooled foam or porous melt. as thistemperature will vary according. to the composition of the material inquestion.

After the foam has passed the cooling bodies and has been rolled ormoulded to the desired shape, I let the final cooling take placecomparatively slowly to avoid formation of tensions in the resultingporous material. A

The' product obtained is very well adapted for use as a building orinsulating material and its porosity and solidity may bevaried asdesired within wide limits. Further my product may with advantage beused as a substitute for reviously known products from slags suc asgranulated slag, slag wool and others.

In the following specific illustration vI give an example of thepreferred way of carrying out my method, reference being made to theaccompanying drawings forming part of this application.

tion I make use of a slag having the following approximate analysis:

Sio2 50% A1203 a() 30% Mc, 5%

b 'I melt "this slag by heating it in any1 coml monly known suitabletype of electric furnace to approximately1400 C. l continuously leadthis molten slag through a channel. 5 into a container 6, which is madeof refractory material capable of withstanding l the slag. The containeris provided with a continuously stirrer, which consists of a double tube7 having cross-pieces 8, 9, 10 and 11 also consist' of double +ubes. Thecross-pieces of the stlrrer when rotated by means of bevelled gears '12and 13 and pulley 14 will pass between similar double tube cross-pieces1.5, 16, 17 and 18, mounted on a double tube 19 in the' wall of thecontainer 6. All of the double tubes are water cooled. The water mayconveniently be introduced respectively, through pipes 20 and 21, andleave the system respectivelyl through tubes 22 and.'23. The doubletubes allow the water to enter through the inner tube and return throughthe outer tube, thus cooling the stirring apparatus. 1 introduce waterinto the container through a pipe 24 at the same time asv the stirrer isrotated. This water will immediately evaporate when touching the hotslag, and a foam will be formed which will rise to the top of thecontainer 6, and pass out through an overflow 25. I regu ate the amount`of water introduced through the pipe 24, so as to give the foam atemperature of approximately 1000o C. From the overflow 25 the foamcascades between two rollers 26 and 27 These are made of iron and arewater cooled, the water entering respectively through pipes 28,28, andleaving through pipes 29, 29 respectively. The rollers are provided withgears 30, and are driven by means of a pulley 31. The openingxbetweenthe two rollers is adjustable and preferably kept about live millimeterswide. The slag or foam will leave the rollersin the form of a sheethaving this thickness. lr regulate the temperature of the rollers so asto cool the mass to about 800 C. Additional cooling means may, ifdesired, be provided and are indicated'in the form of a fluid spray suchas water supplied through the ipe line 33 and .regulated by means of avalve 34. The thin sheet formed between the rollers will drop into`moulds 32, passing slowly under the rollers on a conveyor. The mouldswill thus be filled with porous material, which'will solidify when itLacasse has been cooled down to about 700 C. l have found that in myfoam there is no tendency to form large bubbles in the interior, whenthe whole mass has been cooled to about 800o C. as effected by therollers 26 and 27. The solid pieces of porous material in the moulds areremoved from the conveyor and transferred to a cooling chamber where aslow cooling to ordinary temperature is eiected. The material will thenhave a specific gravity of approximately 0.5. l may however vary theSpecific gravity from 1.5 to 0.1 b varying the composition of the slagand t e intensity of the stirring and foaming operation.

lf the raw material used contains substances which form oisonous orotherwise disagreeable gases, t ese will to a certain extent be resentin the pores of my inal product. ISuch gases are for example H25 an PH3.lhesemay however easily be eliminated by carrying out the foamingoperation in anoxidizing atmosphere.

It is to be understood that theforegoing detailed description of myinvention has been given for clearness of understanding only, and no.undue limitation `should be deduced therefrom, but lthe appended claimsshould be construed as broadly as permissible in view of the prior art.,

lVhat I claim as new and desire to secure by Letters Patent of theUnited States is:

1. In the manufacture of porous materials from melts by producing a foamtherein the process which comprises passing said foam in proximity to acooling bodyl, thereby rapldly lowerin the temperature of the wholemass, an cooling the'foam further until solidification.

2. In the manufacture of porous materials from melts by producing a foamtherein the process which comprises subjecting said foam to the actionof a-'cooling roller, thereby rapidly lowering the temperature of thewhole mass, and cooling the foam further until solidifcation.

3, In the manufacture of porous materials from melts by producing a foamtherein the process which comprises subjecting said foam to the actionof a water cooled ro er, thereby rapidly lowering the temperature ofthewhole mass, and cooling the foam further until solidication.

4. In the manufacture of crous materials from melts by producing a 0amtherein the process which comprises subjecting said foaml to the actionof a water cooledrcller, thereby rapidlylowering the temperature of thewhole mass, directing a stream of water on the mass leaving the roller,and cooling the foam further until solidicaton.

5. ln the manufacture of porous materials from melts by producing a foamtherein the rocess which comprises subjecting said 0am to the action ofa water cooled roller capable of rapidly lowering the temperature of thewhole mass, rolling the foam to form a sheet of a proximately livemillimeters thickness, an cooling the material so treated untilsolidification.

6. In the manufacture of porous materials from melts by producing a foamtherein the process which comprises passing said foam in proximity to acooling body,there by rapidly lowering the temperature of the wholemass, running the cooled foam into a mould, and cooling further untilsolidiication.

7. In `the manufacture of porous matelrials from melts by producing afoam therein the process which comprises subjecting said foam to theaction of a coolingroller, thereby rapidly lowering the temperature ofthe fwhole mass, running the cooled foam 2o into a mould and coolingfurther until solidiication.

8. In the Ymanufacture of porous materials from melts by producing afoam therein the process which comprises subjecting said foam to theaction ofa water cooled roller, thereby rapidly lowering the temperatureof the whole mass, running the cooled foam into a mould, and coolingfurther until solidiication.

9. In the manufacture of porous materials fromV melts by `.producing afoam therein the process which comprlses subjecting said foam to theaction of a water cooled roller, thereby rapidl lowering the temperatureof the who e mass, directing a stream of water on themass leaving theroller, running the cooled foam into a mould -and cooling further untilsolidiiication.

10. In the manufacture of porous mate- 40 rials from melts by producinga foam therein the process which com rises subjecting said foam to theaction o a water cooled roller capable of lowering the temperature ofthe whole mass, rolling the foam to Vform a sheet of approximately fivemillimeters thickness, running the material so treated into a mould andcooling further until solidification.

11. In the manufacture of porous materials from melts by producing afoam therein the process which comprises subjecting such foam having a ltemperature of approximately 1000- C. to the action of a water cooledroller, thereby,- rapidly lowering the temperature of the foam toapproximately 800 C., and cooling the foam further until solidllication.

. 12. In the manufacture of porous mate-v imately 800 C., running thefoam into va mould and cooling further until solidiication.

13. In the manufacture of porous mate-l y rials from'melts by producinga foam therein the process which comprises subjecting such foam havingal temperature of approximately 1000 C. to the action of a water cooledroller capable of rapidly lowering the temperature of the foam toapproximately 800" C., rolling the foam to orm a sheet of' approximatelyfive .millimeters thickness, and cooling the material so treated untilsolidiication. Y

14'. In the manufacture ofporous materials from melts by producing afoam therein the process which comprises subjecting such foam havingatemperature of 1000 C. to the action of a Water cooled roller capable ofrapidly lowering the temperature of the foam to 800 C., rolling the foamto form a sheet of ve millimeters thickness, running the material sotreated into a mould and cooling until solidification.

15. The process of eifectin homogeneous porosity in material formev frommolten slag orthe like which comprises'redu'cing the molten material toa foam of high fluidity, rapidly lowering the temperature of the foam bysubjecting the same to the lco action of a cooling-body, and solidifyingi the material so treated by slow coolin 16. In the manufacture ofporous b ocks from molten slag or the like the process which comprisesreducing the molten material to a foam, lowering the temperature of thefoam and reducing it to sheet lformation 'b of co0 ing rollers, runningthe material so treated into molds and solidifying they same by slowcoolin Signed at Cristiania, Norway, this 20th day of April, 1920.

MATHIAS OVROM SEM.

subjecting the same to the action

